I rode an event called Gravel Macedon last weeked with friends. We rode the 46km route which is big for me as it had 800 metres of climbing.
So "gravel" riding has come to mean riding road ish bicycles on gravel roads with bigger tyres. Possibly with a large hill in the route.
A historically minded aspect might be to consider if the early Tour de France riders were riding paved roads in their entire tour. They were not, so the old is new again.
The big tyres help a lot, and you can choose tyres with knobs that stick up instead of what is called a file tread pattern where the tyre is flat with a few slits.
The lugged steel frame on my bicycle from the 1960s or 1970s has reasonably good clearance for bigger tyres. I can get a 40mm in the front and a 45mm in the rear.
Some more knobby tyre consideration for next year:
- Kenda Alluvium GCT Tyre 700 x 40c (stocked by 99 Bikes)
- Panaracer Gravel King SK (stocked by Merin Cycles UK)
Unfortunately as "gravel" is sort of new and popular, lots of tyres are sold out and also some are only available at their full recommended retail pricing, which is to say they are about $100 australian a tyre!